Riello Array AR 1500 User manual

cod. Doc-0079788 rev. 3 11/2016
Array AR 1000 - AR 1500 - AR 2000 - SERIES 1
US INSTALLATION AND OPERATION MANUAL

2
Dear heating engineer,
Congratulations for proposing a Rboiler. This appliance ensures
maximum comfort for an extended period, with high reliability,
efciency, quality and safety.
This manual provides information that is essential to the in-
stallation of the appliance. Used in conjunction with your own
knowledge and expertise it will enable you to install the appliance
quickly, easily, and correctly.
Please accept our thanks and our congratulations on your choice
of product.
RS.p.A.
CONFORMITY
Commercial Boilers
AHRI Standard BTS-2000
The information contained in this manual is subject to change
without notice from RSpA. Rmakes no warranty of any kind
with respect to this material, including but not limited to implied
warranties of merchantability and tness for a particular appli-
cation. Ris not liable for errors appearing in this manual. Nor
for incidental or consequential damages occurring in connection
with the furnishing, performance, or use of this material.
ENGLISH
RANGE
MODEL CODE
Array AR 1000 20115022
Array AR 1500 20115023
Array AR 2000 20115024
9
WARNING: If the information in these instructions is not fol-
lowed exactly, a re or explosion may result causing property
damage, personal injury or death.
9
WARNING: Do not store or use gasoline or other ammable
vapors and liquids in the vicinity of this or any other appli-
ance.
WHAT TO DO IF YOU SMELL GAS:
− Do not try to light any appliance,
− Do not touch any electrical switch; do not use any phone
in your building,
− Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions,
− If you cannot reach your gas supplier, call the re depart-
ment.
Qualied installer, service agency or the gas supplier must per-
form installation and service.
9
FOR YOUR SAFETY: Improper installation and/or operation
could create carbon monoxide gas in ue gases which could
cause serious injury, property damage, or death. Improper in-
stallation and/or operation will void the warranty.

3
This manual, Cod Doc-0079788 - Rev.3(11/2016) comprises 68 pages
1 GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
1.1 Warnings & cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Emergency shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3 Prolonged shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Receiving the unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Site preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4.1 Installation clearances . . . . . . . . . . . . . . . . . . . . . . . . 7
2.4.2 Setting the Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.5 Boiler location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.6 Supply and return piping . . . . . . . . . . . . . . . . . . . . . . . . 9
2.7 Low water cutoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.8 High limit safety switch . . . . . . . . . . . . . . . . . . . . . . . . 10
2.11.1 Gas Supply Specications . . . . . . . . . . . . . . . . . . . . . 12
2.11.2 Manual Gas Shutoff Valve . . . . . . . . . . . . . . . . . . . . . 12
2.11.3 External Gas Supply Regulator. . . . . . . . . . . . . . . . . . 12
2.11.4 Gas Type Conversion . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.11.5 Adjusting and setting CO2limits. . . . . . . . . . . . . . . . . 13
2.12 AC electrical power wiring . . . . . . . . . . . . . . . . . . . . . . 14
2.12.1 Electrical Power Requirements . . . . . . . . . . . . . . . . . 14
2.13 Field control wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.13.1 Room Thermostat Connection (Enable/Disable) . . . . . 15
2.13.2 Air Damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.13.3 Outdoor Temperature Sensor. . . . . . . . . . . . . . . . . . . 16
2.14 Venting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.15 Combustion air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.15.1 Combustion air from outside the building. . . . . . . . . 20
2.15.2 Combustion air from inside the building. . . . . . . . . . 20
2.15.3 Ducted combustion air . . . . . . . . . . . . . . . . . . . . . . . 20
3 COMMISSIONING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
3.4.1 Conrming the Unit’s Gas Type . . . . . . . . . . . . . . . . . 21
3.4.2 Gas Type Conversion . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.5 Boiler startup procedure . . . . . . . . . . . . . . . . . . . . . . . 22
3.5.1 Minimum Water Flow (Heat Exchanger Protection) . . 23
3.5.2 Heating System Pressure Test. . . . . . . . . . . . . . . . . . . 23
3.6 Boilers’ cascade installation and start-up . . . . . . . . . . 24
3.6.1 Boilers Cascade: Set Boiler Address . . . . . . . . . . . . . . 24
3.6.2 Boilers Cascade: Set Power switch S1 . . . . . . . . . . . . 24
4 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
4.3 Touchscreen control panel menus . . . . . . . . . . . . . . . . 25
4.3.1 Riello Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.3.2 Cascade Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.3.3 Boiler Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.3.4 Module Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.3.5 Performance Screen . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.3.6 Error Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.3.7 Service Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.3.8 Module Test Screen . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5 SHUTDOWN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
5.1 Shutting down the heating system. . . . . . . . . . . . . . . . 28
5.2 Shutting down the heating system in an emergency . . 28
6 ENVIRONMENTAL PROTECTION/DISPOSAL. . . . . . . . . .28
APPENDIX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Appendix A - Wiring diagram. . . . . . . . . . . . . . . . . . . . . . . . 29
Appendix B - Size and connections . . . . . . . . . . . . . . . . . . . 32
Appendix C - Connection diagram . . . . . . . . . . . . . . . . . . . . 34
Appendix D - Technical data . . . . . . . . . . . . . . . . . . . . . . . . 36
Appendix E - Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Appendix F - Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . 39
Appendix G - Head available for the system . . . . . . . . . . . . 40
Appendix H - De-rating for altitude installation . . . . . . . . . 41
Appendix I - Efciency Curves . . . . . . . . . . . . . . . . . . . . . . . 42
Appendix J - Troubleshooting table . . . . . . . . . . . . . . . . . . . 43
Appendix K - BOILER Installation (example drawings) . . . . . 49
Appendix L - Ladder diagram . . . . . . . . . . . . . . . . . . . . . . . 51
Appendix M - Venting size data . . . . . . . . . . . . . . . . . . . . . . 62
Appendix N - Exhaust terminals and Air inlet Clearances . . . 63
Appendix O - Sensor Resistance. . . . . . . . . . . . . . . . . . . . . . 65
The following symbols are used in this manual:
9
CAUTION! = Identies actions that require caution and ad-
equate preparation.
0
STOP! = Identies actions that you MUST NOT do.
CONTENTS

4
GENERAL
1 GENERAL
The RArray AR 1000, AR 1500 and AR 2000 MBH Boilers are
modulating and condensing units. They represent a true industry
advance that meets the needs of today’s energy and environmen-
tal concerns. Designed for application in any closed loop hydronic
system, the Array’s modulating capability relates energy input di-
rectly to uctuating system loads. The turn down ratio for these
models is 10:1 for AR 1000, 15:1 for AR 1500 and 20:1 for AR 2000.
These Array models provide extremely high efciency operation
and are ideally suited for modern low temperature, as well as,
conventional heating systems.
The Array Models AR 1000,AR 1500 and AR 2000 operate within the
following input and output ranges:
Array
model
Input Range (BTU/hr.) Output Range(*) (BTU/hr.)
Minimum Maximum Minimum Maximum
AR 1000 100,000 1,000,000 96,100 961,000
AR 1500 100,000 1,500,000 96,100 1,441,500
AR 2000 100,000 2,000,000 96,100 1,922,000
(*) The output of the boiler is a function of the unit’s ring rate,
return water temperature and BTU content of gas supply.
Array Series of hot water boilers has been designed in compliance
with the CSD-1 code.
When installed and operated in accordance with this Instruction
Manual, these boilers comply with the NOx emission standards
outlined in:
South Coast Air Quality Management District (SCAQMD), Rule 1146.2
Whether used in singular or modular arrangements, the AR 1000,
AR 1500 and AR 2000 offer the maximum venting exibility with
minimum installation space requirements. These Boilers are Cat-
egory IV, positive pressure appliances. Single and/or multiple
breeched units are capable of operation in the following vent
congurations:
− Conventional, Vertical Conventional,
− Sidewall Conventional, Direct Vent,
− Vertical Sealed, Direct Vent, Horizontal
These boilers are capable of being vented utilizing PP, CPVC, Stain-
less steel AL29-4C vent systems.
The Array’s advanced electronics are available in several selectable
modes of operation offering the most efcient operating methods
and energy management system integration.
9
IMPORTANT: Unless otherwise specied, all descriptions and
procedures provided in this Installation & Operation Manual
apply to the Array series of boiler.
1.1 Warnings & cautions
Installers and operating personnel MUST, at all times, observe all
safety regulations. The following warnings and cautions are gen-
eral and must be given the same attention as specic precautions
included in these instructions.
In addition to all the requirements included in this RInstruc-
tion Manual, the installation of units MUST conform with local
building codes, or, in the absence of local codes, ANSI Z223.1 (Na-
tional Fuel Gas Code Publication No. NFPA-54) for gas-red boilers
and ANSI/NFPASB for LP gas-red boilers.
Where applicable, the equipment shall be installed in accordance
with the current Installation Code for Gas Burning Appliances and
Equipment, CSA B149.1, and applicable Provincial regulations for
the class; which should be carefully followed in all cases.
Authorities having jurisdiction should be consulted before instal-
lations are made.
See pages 10 - 12 for important information regarding installation of
units within the Commonwealth of Massachusetts.
9
IMPORTANT: This Instruction Manual is an integral part of the
product and must be maintained in legible condition. It must
be given to the user by the installer and kept in a safe place
for future reference.
9
WARNING: Do not use matches, candles, ames, or other
sources of ignition to check for gas leaks.
9
WARNING: Fluids under pressure may cause injury to person-
nel or damage to equipment when released. Be sure to shut
off all incoming and outgoing water shutoff valves. Careful-
ly decrease all trapped pressures to zero before performing
maintenance.
9
WARNING: Before attempting to perform any maintenance on
the unit, shut off all gas and electrical inputs to the unit.
9
WARNING: The exhaust vent pipe of the unit operates under
a positive pressure and therefore must be completely sealed
to prevent leakage of combustion products into living spaces.
9
WARNING: Electrical voltages up to 120 vac maybe used in this
equipment. Therefore the cover on the unit’s power box (lo-
cated behind the front panel door) must be installed at all
times, except during maintenance and servicing.
9
CAUTION: Many soaps used for gas pipe leak testing are cor-
rosive to metals. The piping must be rinsed thoroughly with
clean water after leak checks have been completed.
0
CAUTION: DO NOT use this boiler if any part has been under wa-
ter. Call a qualied service technician to inspect and replace
any part that has been under water.

5
GENERAL
1.2 Emergency shutdown
If overheating occurs or the gas supply fails to shut off, close the
manual gas shutoff valve (Fig. 1) located external to the unit.
NOTE: The Installer must identify and indicate the location of the
emergency shutdown
Fig. 1 Manual Gas Shutoff Valve
1.3 Prolonged shutdown
After prolonged shutdown, it is recommended that the startup
procedures and the safety device test procedures of this manual
be performed, to verify all system-operating parameters. If there
is an emergency, turn off the electrical power supply to the R
boiler and close the manual gas valve located upstream the unit.
The installer must identify the emergency shut-off device.
IMPORTANT - FOR MASSACHUSETTS INSTALLATIONS
Boiler Installations within the Commonwealth of Massachusetts
must conform to the following requirements:
− Boiler must be installed by a plumber or a gas tter who is
licensed within the Commonwealth of Massachusetts.
− Prior to unit operation, the complete gas train and all con-
nections must be leak tested using a non-corrosive soap.
− The vent termination must be located a minimum of 4 feet
above grade level. If side-wall venting is used, the installa-
tion must conform to the following requirements extracted
from 248 CMR 5.08 (2):
(a) For all side wall horizontally vented gas fueled equipment in-
stalled in every dwelling, building or structure used in whole or in
part for residential purposes, including those owned or operated
by the Commonwealth and where the side wall exhaust vent ter-
mination is less than seven (7) feet above nished grade in the
area of the venting, including but not limited to decks and porch-
es, the following requirements shall be satised:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS
At the time of installation of the side wall horizontal vented gas
fueled equipment, the installing plumber or gastter shall ob-
serve that a hard wired carbon monoxide detector with an alarm
and battery back-up is installed on the oor level where the gas
equipment is to be installed.
In addition, the installing plumber or gastter shall observe that a
battery operated or hard wired carbon monoxide detector with an
alarm is installed on each additional level of the dwelling, build-
ing or structure served by the side wall horizontal vented gas fu-
eled equipment. It shall be the responsibility of the property own-
er to secure the services of qualied licensed professionals for the
installation of hard wired carbon monoxide detectors.
a. In the event that the side wall horizontally vented gas fueled
equipment is installed in a crawl space or an attic, the hard
wired carbon monoxide detector with alarm and battery back-
up may be installed on the next adjacent oor level.
b. In the event that the requirements of this subdivision cannot
be met at the time of completion of installation, the owner
shall have a period of thirty (30) days to comply with the above
requirements; provided, however, that during said thirty (30)
days period, a battery operated carbon monoxide detector
with an alarm shall be installed.
2. APPROVED CARBON MONOXIDE DETECTORS
Each carbon monoxide detector as required in accordance with
the above provisions shall comply with NFPA 720 and be ANSI/UL
2034 listed and IAS certied.
3. SIGNAGE
A metal or plastic identication plate shall be permanently
mounted to the exterior of the building at a minimum height of
eight (8) feet above grade directly in line with the exhaust vent
terminal for the horizontally vented gas fueled heating appliance
or equipment.
The sign shall read, in print size no less than one-half (1/2) inch in
size, “GAS VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS”.
4. INSPECTION
The state or local gas inspector of the side wall horizontally vented
gas fueled equipment shall not approve the installation unless,
upon inspection, the inspector observes carbon monoxide detec-
tors and signage installed in accordance with the provisions of 248
CMR 5.08(2)(a)1 through 4.
(b) EXEMPTIONS:
The following equipment is exempt from 248 CMR 5.08(2)(a)1
through 4:
1. The equipment listed in Chapter 10 entitled “Equipment Not
Required To Be Vented” in the most current edition of NFPA 54
as adopted by the Board; and
2. Product Approved side wall horizontally vented gas fueled
equipment installed in a room or structure separate from the
dwelling, building or structure used in whole or in part for res-
idential purposes.

6
GENERAL
(c) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYS-
TEM PROVIDED
When the manufacturer of Product Approved side wall horizon-
tally vented gas equipment provides a venting system design or
venting system components with the equipment, the instructions
provided by the manufacturer for installation of the equipment
and the venting system shall include:
1. Detailed instructions for the installation of the venting system
design or the venting system components; and
2. A complete parts list for the venting system design or venting
system.
(d) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYS-
TEM NOT PROVIDED
When the manufacturer of a Product Approved side wall horizon-
tally vented gas fueled equipment does not provide the parts for
venting the ue gases, but identies “special venting systems”,
the following requirements shall be satised by the manufacturer:
1. The referenced “special venting system” instructions shall be
included with the appliance or equipment installation instruc-
tions; and
2. The “special venting systems” shall be Product Approved by the
Board, and the instructions for that system shall include a parts
list and detailed installation instructions.
(e) A copy of all installation instructions for all Product Approved
side wall horizontally vented gas fueled equipment, all venting in-
structions, all parts lists for venting instructions, and/or all venting
design instructions shall remain with the appliance or equipment
at the completion of the installation.
[End of Extracted Information From 248 CMR 5.08 (2)]
2 INSTALLATION
2.1 Introduction
This Chapter provides the descriptions and procedures necessary
to unpack, inspect and install the RArray Boiler Model AR 1000,
AR 1500 and AR 2000.
2.2 Receiving the unit
Each Array Boiler System is shipped as a single crated unit. The unit
must be moved with the proper lifting equipment for safety and to
avoid equipment damage. The unit should be completely inspect-
ed for evidence of shipping damage and shipment completeness
at the time of receipt from the carrier and before the bill of lading
is signed.
NOTE: Ris not responsible for lost or damaged freight. Any vi-
sual damage to the packaging materials should be made clear to
the delivering carrier.
2.3 Unpacking
Carefully unpack the unit, pay particular attention not to damage
the unit enclosure when cutting away packaging materials.
After unpacking, a close inspection of the unit should be made
to ensure that there is no evidence of damage. The freight carrier
should be notied immediately if any damage is detected.
The following accessories come standard with each unit and are
either packed separately within the unit’s shipping container or
are factory installed on the unit:
− Pressure/Temperature Gauge
− ASME Pressure Relief Valves
− Condensate Drain Traps
− Outdoor Sensor
− System Supply Sensor (length: 20”)
− Connection Cable between 905PB internal display and
905MN boards
− Stainless steel Air intake adapter 6”
When optional accessories are ordered, they may be packed with-
in the unit’s shipping container, factory installed on the unit, or
packed and shipped in a separate container. Any standard or op-
tional accessories shipped loose should be identied and stored
in a safe place until ready for installation or use.
2.4 Site preparation
Ensure that the site selected for installation of the Array AR 1000,
AR 1500 and AR 2000 Boiler includes:
− Access to AC Input Power at 120 VAC, Phase-Phase, 60 Hz @
24 FLA
− Access to Natural Gas line at a recommended minimum
pressure of 8 inches W.C. for 1,000,000 BTU/hr energy in-
putfortheAR1000,1,500,000BTU/hrenergyinputfortheAR1500
OR 2,000,000 BTU/hr energy input for the AR 2000.

7
INSTALLATION
2.4.1 Installation clearances
The Array models AR 1000, AR 1500 and AR 2000 are packaged in
an enclosure having identical footprint but different height.
The unit must be installed with the prescribed clearances for ser-
vice as shown in Fig. 2 and Fig. 3. The minimum clearance dimen-
sions, required by R, are listed below. However, if Local Building
Codes require additional clearances, these codes shall supersede
R’s requirements.
Minimum acceptable clearances required are as follows:
− Sides: 24 inches
− Front: 31.5 inches
− Rear: 24 inches
− Top: 24 inches
All gas piping, water piping and electrical conduit or cable must
be arranged so that they do not interfere with the removal of any
panels, or inhibit service or maintenance of the unit.
24”
24”
24”
24”
31.5”
60.8”
67.2”
Fig. 2 Array AR 1000, AR 1500 Clearances
24”
24”
24”
31.5”
24”
83”
60.8”
Fig. 3 Array AR 2000 Clearances
9
WARNING: Keep the unit area clear and free from all combus-
tible materials and ammable vapors or liquids.
9
CAUTION: While packaged in the shipping container, the unit
must be moved by pallet jack or forklift from the SIDE ONLY.
FOR MASSACHUSSETTS ONLY:
For Massachusetts installations, the unit must be installed by a
plumber or gastter licensed within the Commonwealth of Mas-
sachusetts. In addition, the installation must comply with all re-
quirements specied in “Warnings & cautions” pag. 4.

8
INSTALLATION
2.4.2 Setting the Unit
Remove the top and side wooden panels, the plastic lm and the
polystyrene sheets. Remove the lag screws securing the unit to the
shipping skid. Lift the unit off the shipping skid with a forklift and
position it on the oor in the desired location.
9
WARNING: When lifting or moving the boiler: do not attempt
to manipulate the boiler using the top water anges or any
other component of the boiler.
9
WARNING: When lifting or moving the boiler with a forklift:
make sure the forks are longer than the boiler size (width or
depth) so that forks stick out as per Fig. 4.
Fig. 4 Array AR 1000, AR 1500 and AR 2000 Forklift Handling
If a crane is required, the boiler must be lifted through bands.
9
WARNING: When lifting the boiler with crane: use bands, no
chains. Bands must comply with federal, state and local rules.
9
WARNING: When lifting the boiler with crane: the bands must
be positioned according to the Fig. 5 and Fig. 6.
In multiple unit installations, it is important to plan the position
of each unit in advance. Sufcient space for piping connections
and future service/maintenance requirements must also be taken
into consideration. All piping must include ample provisions for
expansion.
FRONT
12.6”31.1”
Fig. 5 Array AR 1000, AR 1500 Crane Lifting Handling
12.6”29.5”
FRONT
Fig. 6 Array AR 2000 Crane Lifting Handling

9
INSTALLATION
The unit must be installed on a concrete at oor, with no gra-
dient in any direction, to ensure proper condensate and water
drainage (see Fig. 7). If anchoring the unit, refer to Fig. 8 for anchor
locations.
Fig. 7 Array AR 1000, AR 1500 and AR 2000 Installation
30.7”
2.8”
2.8”
58.2”
Fig. 8 Array AR 1000, AR 1500 and AR 2000 Anchoring bolts
2.5 Boiler location
− This boiler is suitable for indoor installations.
− To operate properly and safely this boiler requires a con-
tinuous supply of air for combustion. Install this boiler in a
clean, dry location with adequate air supply.
− Do not locate this boiler in an area where it will be subject
to freezing.
− The boiler should be located close to a oor drain in an
area where leakage from the appliance or connections will
not result in damage to the adjacent area or to lower oors
in the structure.
− DO NOT install this appliance in any location where gasoline
or ammable vapors are likely to be present.
− DO NOT install this appliance on top of carpet ooring.
− Appliance must be installed on a level oor.
− Maintain required clearances from combustible surfaces.
2.6 Supply and return piping
The Array Boiler utilizes 3” anges for models AR 1000 and AR 1500
and 4” anges for model AR 2000 for the water system supply and
return piping connections. The physical location of the supply and
return piping connections is on the top of the unit as shown in
Fig. 9.
Water
Return
Water
Supply
Gas
connection
Fig. 9 Array AR 1000, AR 1500 and AR 2000 Connections

10
INSTALLATION
Excessive water hardness causing a lime buildup in the stainless
steel coils or tubes is not a fault of the appliance and is not cov-
ered by warranty. Water hardness must fall within the following
limits:
STEEL BOILERS - With furnace power > 500kBTU/h
Water used
for rst lling
Water with
system operating
ph 6 - 8 7.5 – 9.5
Hardness ppm < 50 < 50
Electrical Conduc-
tivity ppm < 67
Chlorides ppm < 10
Sulphides ppm < 10
Nitrides ppm < 10
Oxygen in Solution ppm
Iron ppm < 0.5
− Use only untreated water to ll the system.
− Do not use TSP (tri-sodium phosphate).
− Do not use ll water treated with salt bedding type ex-
changers (ion exchanger).
− Never introduce non-approved boiler treatment or similar
additives.
− Consult a local water treatment specialist for recommenda-
tions if any of the above is outside the stated ranges.
− When using oxygen permeable PEX, the system must be
separated from the boiler by a heat exchanger.
− A correctly sized and working expansion vessel must be in-
stalled.
− Do not exceed the maximum permissible ow rate through
the boiler. Excessive ow can cause erosion damage to the
heat exchanger.
9
CAUTION: Before connecting the boiler to the heating system,
ush the heating system to remove sediment, ux, dirt, and
other foreign matter. The heat exchanger may be damaged by
sediment or corrosion.
9
CAUTION: Do not use cleaning uids that are not compatible
with the boiler materials, including acids (e.g. hydrochloric
acid and similar ones) at any concentration.
9
CAUTION: Introducing fresh water to the system increases the
oxygen presence and can cause corrosion of metallic compo-
nents. Immediately repair any drips or leaks in the system to
avoid constant introduction of air into the system.
9
CAUTION: Excessive uctuation in pressure changes in the sys-
tem can cause fatigue and stress on the heat exchanger. This
is detrimental to the integrity of the boiler and system com-
ponents, it is mandatory to maintain a constant operating
pressure.
9
CAUTION: For freeze protection use only propylene glycol, with
scale inhibitors, with a maximum volume [concentration] of
50% of glycol. Frost protection and inhibitor level has to be
checked annually during the regular scheduled maintenance
of the condensing boiler.
A minimum water pressure is required for optimum performance.
Minimum water pressure required: 7.25 psi (0.5 bar).
2.7 Low water cutoff
A low water cut off (LWCO) is installed on each boiler.
To check the functionality of LWCO go to the 905PB inner display,
access the Settings menu, select Test mode, and then click on
LWCO1. On the screen will appear the error “MN: Low Water Cutoff
Error”.
At this point press the reset button. The error will turn off.
2.8 High limit safety switch
A high limit safety switch is installed on each module of the boiler.
To simulate a high limit lockout at 208°F go to the 905PB inner
display, access the Settings menu, select Test mode, then click on
Max temp.
The control will display “MN: Max. Thermostat Lock Error”.
At this point press the reset button on the removable display to
restart the module.
The same test can be carried out as described at section “4.3.8
Module Test Screen” pag. 27.
2.9 Pressure relief valve installation
ASME rated Pressure Relief Valves are factory installed in each Array
Boiler. The pressure rating for the relief valves is 75 PSI. The relief
valves are installed on each hot water horizontal manifold of the
boiler as shown in Fig. 10. The relief valves drain piping must be
connected to a nearby oor drain. In multiple unit installations
the discharge lines must not be manifolded together.
Each must be individually run to a suitable discharge location. Re-
lief valves should be manually operated at least once a year. If
a relief valve discharges periodically, this may be due to thermal
expansion in a closed water supply system.
Contact the water supplier or local plumbing inspector on how to
correct this situation.
Do not plug the relief valve.
75PSI Relief valve
(one for each module)
Fig. 10 Pressure Relief Valve Location